@keyframes fade-in {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fade-in-down {
    from {
        opacity: 0;
        @include transform(translateY(-$spacing-unit));
    }
    to {
        opacity: 1;
        @include transform(translateY(0));
    }
}